Strengthening the evidence base for precision medicine through the utilization of real-world data and real-world evidence: a narrative review from the U.S. perspective.

Abstract

The expansion of precision medicine has shifted toward individualized care tailored to a patient's genetic profile. While randomized controlled trials (RCTs) remain the gold standard for establishing efficacy, they often struggle to reflect the phenotypic diversity of patients in routine clinical practice. This paper explores the role of Real-World Data (RWD) and Real-World Evidence (RWE) in bridging this translational gap. A structured literature search identified peer-reviewed articles examining RWE applications in identifying rare genetic targets, informing clinical trial design, and supporting U.S. Food and Drug Administration (FDA) regulatory decisions. This review synthesizes recent regulatory advances through early 2026, including frameworks supporting the use of aggregated RWD that expand large-scale, multi-institutional evidence generation. RWE provides a scalable mechanism for identifying rare genetic variants and validating biomarker-driven therapies across heterogeneous patient populations while enabling longitudinal assessment of natural disease history and treatment safety. Operational successes in oncology, transplant medicine, and rare diseases demonstrate regulatory acceptance of RWE alongside critical challenges in data standardization, interoperability, and bias mitigation through causal inference frameworks, including target trial emulation. RWD and RWE serve as necessary complements to RCTs, providing the hybrid evidentiary framework needed to realize precision medicine's potential. Precision medicine treats patients based on their unique genetic makeup. While clinical trials test whether a drug works, they often do not reflect the wide variety of patients seen in everyday care. This paper looks at how Real-World Data (RWD) and Real-World Evidence (RWE) from sources like electronic health and medical records, insurance claims, and genetic databases can help fill that information gap. RWE helps researchers find rare genetic targets, design better clinical trials, and support FDA drug approvals across diverse patient populations. It also helps track how diseases progress and whether treatments stay safe over time. However, challenges remain around combining data from different sources and reducing research errors or unintentional bias. Ultimately, RWD and RWE are critical partners to complement traditional clinical trials, and improving how the data is shared and analyzed will be key to making personalized medicine work for more patients.